Our Studies

We conduct multiple research studies — the COVID Symptom Study, now known as the ZOE Health Study, and PREDICT, which is the largest in-depth nutrition study in the world, conducted with scientists from Massachusetts General Hospital, Stanford Medicine, Harvard T.H. Chan School of Public Health, and King’s College London.

Learn more


Predict 1 Study


We measured biological responses to specific foods in 1,106 people over 14 days, measuring blood glucose and fat levels, activity, inflammation, sleep and gut microbiome diversity. Our findings have been published in Nature Medicine in June 2020.

ParticipantParticipants: 1,106

Start dateStarted: June 2018

Completion dateCompleted: September 2019

In partnership with researchers at:

Kings College LondonMassachusetts General Hospital
Predict 2 Study


An expanded home-based study that opened in June 2019. We recruited 1,200 volunteers across the US, measuring nutritional responses to food over a period of 11 days.

ParticipantParticipants: 1,200

Start dateStarted: June 2019

Completion dateCompleted: March 2020

In partnership with researchers at:

Standford MedicineMassachusetts General Hospital
Predict 3 Study


The PREDICT 3 study will build on previous research in over 2,000 individuals to further refine machine learning models that predict individual responses to foods, with the aim of advancing precision nutrition science and individualized dietary advice.

ParticipantParticipants: 100,000

Start dateStarted: July 2020

Completion dateCompleted: December 2023

In partnership with researchers at:

Kings College LondonMassachusetts General Hospital

ZOE Health & Nutrition studies

Nature Medicine

Effects of a personalized nutrition program on cardiometabolic health: a randomized controlled trial

May 2024

European Journal of Nutrition

Snack quality and snack timing are associated with cardiometabolic blood markers: the ZOE PREDICT study

September 2023

European Journal of Nutrition

Exploring the relationship between social jetlag with gut microbial composition, diet and cardiometabolic health, in the ZOE PREDICT 1 cohort

August 2023

World of Microbiome Conference

Keynote Lecture: Personalisation and the human microbiome

October 2023

EMBL Conference

Unraveling the complex interplay between the human gut microbiome, diet, and cardiometabolic health from the ZOE PREDICT studies. View PDF.

September 2023

BMC Medicine

Plasma protein N-glycome composition associates with postprandial lipaemic response

July 2023


Characterisation of fasting and postprandial NMR metabolites: Insights from the ZOE PREDICT 1 study

June 2023

Nature Medicine

Cardiometabolic health, diet and the gut microbiome: A meta-omics perspective

March 2023

Cell Reports Medicine

The secondary bile acid isoursodeoxycholate correlates with post-prandial lipemia, inflammation, and appetite and changes post-bariatric surgery

April 2023

Nature Biotechnology

Extending and improving metagenomic taxonomic profiling with uncharacterized species using MetaPhlAn 4

February 2023

Nature Communications

How people wake up is associated with previous night’s sleep together with physical activity and food intake

November 2022


Menopause is associated with postprandial metabolism, metabolic health and lifestyle: The ZOE PREDICT study

November 2022


Postprandial responses to a standardised meal in hypertension: The mediatory role of visceral fat mass

October 2022

American Journal of Clinical Nutrition

Validity of continuous glucose monitoring for categorizing glycemic responses to diet and its potential for personalized nutrition

June 2022


Impact of insufficient sleep on dysregulated blood glucose control under standardised meal conditions

February 2022

Nature Food

Diet and lifestyle behaviour disruption related to the pandemic was varied and bidirectional among US and UK adults participating in the ZOE COVID Study

16th December 2021


Diet quality and risk and severity of COVID-19: A prospective cohort study

6th September 2021

Journal of Hypertension

Gut microbiome diversity and composition is associated with hypertension in women

1st September 2021

American Journal of Clinical Nutrition

Meal-induced inflammation: Postprandial insights from the PREDICT study in 1,000 participants

8th June 2021


Modest effects of dietary supplements during the COVID-19 pandemic: Insights from 445,850 users of the COVID-19 Symptom Study app

19th April 2021

Nature Metabolism

Postprandial glycemic dips predict appetite and caloric intake and are determined by meal content and insulin secretion in healthy individuals: the PREDICT 1 study.

12th April 2021

BMC Medicine

High intake of vegetables is linked to lower white blood cell profile and the effect is mediated by the gut microbiome

11th February 2021

Nature Medicine

Microbiome connections with host metabolism and habitual diet from 1,098 deeply phenotyped individuals

11th January 2021

Nature Medicine

Human postprandial responses to food and potential for precision nutrition

11th June 2020


Blue poo: Impact of gut transit time on the gut microbiome using a novel marker

15th March 2020

Protocol Exchange

Personalised REsponses to DIetary Composition Trial (PREDICT): An intervention study to determine inter-individual differences in postprandial response to foods

14th January 2020


The Lancet

Risk of long COVID associated with delta versus omicron variants of SARS-CoV-2

18th June 2022

The Lancet

Risk of hospitalisation and death in children with SARS-CoV-2 delta (B.1.612.2) infection

29th March 2022

Nature Communications

Self-reported COVID-19 vaccine hesitancy and uptake among participants from different racial and ethnic groups in the United States and United Kingdom

1st February 2022

The Lancet eClinical Medicine

Disentangling post-vaccination symptoms from early COVID-19

1st December 2021

Scientific Data

Accessible data curation and analytics for international-scale citizen science datasets

22nd November 2021

The Journals of Gerontology: Series A

Individual factors including age, BMI, and heritable factors underlie temperature variation in sickness and in health: An observational, multi-cohort study

5th October 2021

Journal of Neurology, Neurosurgery and Psychiatry

Anxiety and depression symptoms after COVID-19 infection: Results from the COVID Symptom Study app

28th September 2021


Estrogen and COVID-19 symptoms: Associations in women from the COVID Symptom Study

10th September 2021

The Lancet Infectious Diseases

Risk factors and disease profile of post-vaccination SARS-CoV-2 infection in UK users of the COVID Symptom Study app: A prospective, community-based, nested, case-control study

1st September 2021

The Lancet Child & Adolescent Health

Illness duration and symptom profile in symptomatic UK school-aged children tested for SARS-CoV-2

3rd August 2021

The Lancet Digital Health

Early detection of COVID-19 in the UK using self-reported symptoms: A large-scale, prospective, epidemiological surveillance study

29th July 2021

The Lancet Digital Health

Anosmia, ageusia, and other COVID-19-like symptoms in association with a positive SARS-CoV-2 test, across six national digital surveillance platforms: An observational study

22nd July 2021

The Lancet eClinical Medicine

Race, ethnicity, community-level socioeconomic factors, and risk of COVID-19 in the United States and the United Kingdom

16th July 2021

Nature Communications

Association of social distancing and face mask use with risk of COVID-19

18th June 2021

Nature Medicine

Author Correction: Attributes and predictors of long COVID

27th May 2021

The Lancet Infectious Diseases

Vaccine side-effects and SARS-CoV-2 infection after vaccination in users of the COVID Symptom Study app in the UK: A prospective observational study

27th April 2021

The Lancet Public Health

Changes in symptomatology, reinfection, and transmissibility associated with the SARS-CoV-2 variant B.1.1.7: An ecological study

12th April 2021

Scientific Reports

Symptoms and syndromes associated with SARS-CoV-2 infection and severity in pregnant women from two community cohorts

25th March 2021

Science Advances

Symptom clusters in COVID-19: A potential clinical prediction tool from the COVID Symptom Study app

19th March 2021

Nature Medicine

Attributes and predictors of long COVID

10th March 2021

Journal of Infection

Optimal symptom combinations to aid COVID-19 case identification: Analysis from a community-based, prospective, observational cohort

12th February 2021


A prediction model to prioritize individuals for a SARS-CoV-2 test built from national symptom surveys

12th February 2021


Diagnostic value of cutaneous manifestation of SARS-CoV-2 infection

14th January 2021

Frontiers in Medicine

Effects of environmental factors on severity and mortality of COVID-19

10th January 2021


Current smoking and COVID-19 risk: Results from a population symptom app in over 2.4 million people

5th January 2021


Geo-social gradients in predicted COVID-19 prevalence in Great Britain: Results from 1,960,242 users of the COVID-19 Symptoms Study app

29th December 2020

The Lancet Public Health

Detecting COVID-19 infection hotspots in England using large-scale self-reported data from a mobile application: A prospective, observational study

3rd December 2020

Twin Research and Human Genetics

Self-reported symptoms of COVID-19, including symptoms most predictive of SARS-CoV-2 infection, are heritable

December 2020

The Lancet

Widespread smell testing for COVID-19 has limited application – Authors' reply

3rd November 2020

The Lancet Healthy Longevity

Tackling immunosenescence to improve COVID-19 outcomes and vaccine response in older adults

November 2020

Journal of Infection

Estimates of the rate of infection and asymptomatic COVID-19 disease in a population sample from SE England

14th October 2020

Age and Ageing

Probable delirium is a presenting symptom of COVID-19 in frail, older adults: A cohort study of 322 hospitalised and 535 community-based older adults

28th September 2020

The Oncologist

Cancer and risk of COVID-19 through a general community survey

26th August 2020

The Lancet Public Health

Risk of COVID-19 among front-line health-care workers and the general community: A prospective cohort study

31st July 2020

Cancer Epidemiology, Biomarkers & Prevention

The COronavirus Pandemic Epidemiology (COPE) Consortium: A call to action

1st July 2020

The Lancet

Quantifying additional COVID-19 symptoms will save lives

4th June 2020

Nature Medicine

Real-time tracking of self-reported symptoms to predict potential COVID-19

11th May 2020


Rapid implementation of mobile technology for real-time epidemiology of COVID-19

5th May 2020